It is known that exhaled breath is commonly used in alcohol testing and today's technology makes it possible to perform on-site breath testing with legally defensible results using electrochemical sensory. An emerging technology is using infrared spectroscopy.
However, testing for other illicit drugs of abuse still requires blood or urine samples. Alternatively specimens comprising hair, sweat or oral fluid could be used. Blood sampling is invasive and requires medically trained personnel, why test subject often have to be transported to a hospital for sampling. This is time and effort consuming. With long lead times the test result will be too old. Urine sampling is considered intruding on personal integrity and must be done under supervision of a nurse or a doctor. Even other issues related to samples and specimen taken from a subject to be tested arise. For instance for blood samples, and especially for urine samples are at risk of the subject exchanging the samples or using clean samples from another subject to avoid being discovered with traces of illicit drugs.
Result from a study related to this topic and performed on Ireland can be found in: Results and conclusions from Injury Prevention 2006; 12:404-408. doi: 10.1136/ip.2006.013177. 33.1% of the drivers under the legal limit for alcohol tested positive for one or more of the relevant drugs, and the corresponding figures of drivers over the limit was 14.2. Among drivers who had minimal blood alcohol levels, 67.9% were taking at least one type of drug. The prevalence of taking drugs reduced steadily as alcohol concentrations increased, but still remained as high as 11.1% for drivers with blood alcohol concentrations 0.200 mg/100 ml. Being under the limit for alcohol, stopped in a city area, stopped between 6 am and 4 pm, or 4 pm and 9 pm, and being of a younger age were each independently associated with drug positivity.
Conclusions of the study point out the serious need for a readily available drug test in addition to today's alcohol tests. There are immediate implications for the evidential breath alcohol program and for checkpoints; in the event of a nil or low alcohol reading being obtained, a separate blood or urine specimen should be sought for analysis, which is currently non-routine. However, obtaining blood or urine specimen as a routine test for all drivers in regular traffic controls is not a feasible alternative due to the issues pointed out above.
Another investigation related to this topic is described in: Investigate of the prevalence and characteristics of abusive drug exposure among non-fatal motor vehicle driver casualties in Hong Kong. (Hong Kong Med J 2010; 16:246-51). The Setting for this study was a Designated trauma centre/regional accident and emergency department in Hong Kong. Investigated subjects were Non-fatal motor vehicle driver casualties who presented to the trauma centre from 1 Jan. 2007 to 31 Dec. 2007.
Results from drug screening that was performed in 395 injured drivers show 10% of whom tested positive for the drugs of interest. Ketamine was the most commonly detected abusive substance (found in 45% of the subjects). A significantly higher proportion of young drivers (aged<25 years) screened positive (odds ratio=2.3; 95% confidence interval, 1.0-5.2; P=0.04), with the rate being 21%.
The presence of these drugs in urine was related to the time of occurrence of the crash; those occurring between midnight and dawn revealed a trend towards a higher proportion of casualties testing drug-positive (odds ratio=2.2; 95% confidence interval, 0.9-5.3; P=0.07). There were no significant differences in the frequency of persons testing positive for the screened drugs with respect to gender, class of motor vehicle driven, or the day of the week on which the crash occurred
This study further supports the urgent need for a convenient, reliable and quick detection of drugs in subjects. An apparatus, system and/or method would be advantageous which allows at least for a pre-screening of subjects to identify subjects under the influence of drugs. These subjects may then further investigated, e.g. by obtaining blood or urine specimens for analysis.
In addition, there is a need for being able to detect other molecules from exhaled breath as well. For instance biomarker compounds indicative of various kinds of diseases would be desirable to being able to detect.
However, as there are a multitude of different analytes in exhaled breath, most in very low amounts or only as traces, it is a challenge to have a measurement system or method that is sufficiently sensitive to discern between all these different analytes.
Thus, there is a need to provide a non-invasive, not-specimen based apparatus, system and/or method for detecting the presence or determining the quantitative amount of analytes, in particular at least one drug substance in a subject.
Hence, an improved apparatus, system and/or method for on-site sampling of a subject for analytes, in particular drug substances is desired. Such an apparatus, system and/or method for sampling the subject for illicit drugs of abuse and/or medical drugs would be desired. The apparatus, system and/or method should be efficient, non-bulky, user friendly both for operators and the subject. It should further be not intruding and not invasive. It should preferably be able to discern between various analytes.